From 36dec540a6af5f6355b9a97f100545bbf47c53a7 Mon Sep 17 00:00:00 2001
From: Krmjn09 <mahajankriti672@gmail.com>
Date: Tue, 17 Jun 2025 16:53:53 +0530
Subject: [PATCH 1/2] Added Logic For Alias and Extra Type Info

---
 demo/node/rntuple_test.js | 18 +++++++++++++++
 modules/rntuple.mjs       | 47 +++++++++++++++++++++++++++++++++++++++
 2 files changed, 65 insertions(+)

diff --git a/demo/node/rntuple_test.js b/demo/node/rntuple_test.js
index 77d451d47..641346997 100644
--- a/demo/node/rntuple_test.js
+++ b/demo/node/rntuple_test.js
@@ -41,7 +41,17 @@ else {
       console.error(`FAILURE: Field ${i} is missing name or type`);
     else
       console.log(`OK: Field ${i}: ${field.fieldName} (${field.typeName})`);
+    if (i === 0) {
+      if (field.fieldName !== 'Category' || field.typeName !== 'std::int32_t') 
+        console.error(`FAILURE: First field should be 'Category (std::int32_t)' but got '${field.fieldName} (${field.typeName})'`);
+      
+    } else if (i === rntuple.builder.fieldDescriptors.length - 1){
+      if (field.fieldName !== 'Nation' || field.typeName !== 'std::string')
+        console.error(`FAILURE: Last field should be 'Nation (std::string)' but got '${field.fieldName} (${field.typeName})'`);
+      
+    }
   }
+  
 }
 
 // Column Check
@@ -56,6 +66,14 @@ else {
       console.error(`FAILURE: Column ${i} is missing fieldId`);
     else
       console.log(`OK: Column ${i} fieldId: ${column.fieldId} `);
+    if (i === 0) {
+      if (column.fieldId !== 0)
+        console.error(`FAILURE: First column should be for fieldId 0 (Category)`);
+    } else if (i === rntuple.builder.columnDescriptors.length - 1){
+      if (column.fieldId !== 10)
+        console.error(`FAILURE: Last column should be for fieldId 10 (Nation)`);
+    }
   }
 }
 
+
diff --git a/modules/rntuple.mjs b/modules/rntuple.mjs
index fb252b250..687e38cd5 100644
--- a/modules/rntuple.mjs
+++ b/modules/rntuple.mjs
@@ -130,6 +130,10 @@ deserializeHeader(header_blob) {
    
   // List frame: list of column record frames
   this._readColumnDescriptors(reader);
+  // Read alias column descriptors
+  this._readAliasColumn(reader);
+  // Read Extra Type Information
+  this._readExtraTypeInformation(reader);
   }
 
 deserializeFooter(footer_blob) {
@@ -267,6 +271,49 @@ _readColumnDescriptors(reader) {
   }
  this.columnDescriptors = columnDescriptors;
 }
+_readAliasColumn(reader){
+  const aliasColumnListSize = reader.readS64(); // signed 64-bit
+  const aliasListisList = aliasColumnListSize < 0;
+  if (!aliasListisList)
+    throw new Error('Alias column list frame is not a list frame, which is required.');
+  const aliasColumnCount = reader.readU32(); // number of alias column entries
+  console.log('Alias Column List Count:', aliasColumnCount);
+  const aliasColumns = [];
+  for (let i = 0; i < aliasColumnCount; ++i){
+  const aliasColumnRecordSize = reader.readS64(),
+    physicalColumnId = reader.readU32(),
+    fieldId = reader.readU32();
+    console.log(`Alias Column Record Size: ${aliasColumnRecordSize}`);
+    aliasColumns.push({
+      physicalColumnId,
+      fieldId
+    });
+  }
+  this.aliasColumns = aliasColumns;
+}
+_readExtraTypeInformation(reader) {
+  const extraTypeInfoListSize = reader.readS64(); // signed 64-bit
+  const isList = extraTypeInfoListSize < 0;
+
+  if (!isList)
+    throw new Error('Extra type info frame is not a list frame, which is required.');
+
+  const entryCount = reader.readU32(); 
+  console.log('Extra Type Info Count:', entryCount);
+
+  const extraTypeInfo = [];
+  for (let i = 0; i < entryCount; ++i) {
+    const extraTypeInfoRecordSize = reader.readS64(),
+    contentId = reader.readU32(),
+    typeVersion = reader.readU32();
+    console.log(`Extra Type Info Record Size: ${extraTypeInfoRecordSize}`);
+    extraTypeInfo.push({
+      contentId,
+      typeVersion
+    });
+  }
+  this.extraTypeInfo = extraTypeInfo;
+}
 
 }
 

From 71ac6a99afefb8faf6f8881efbb48b01f3655c4c Mon Sep 17 00:00:00 2001
From: Krmjn09 <mahajankriti672@gmail.com>
Date: Tue, 17 Jun 2025 16:57:05 +0530
Subject: [PATCH 2/2] Added Null case for column

---
 demo/node/rntuple_test.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/demo/node/rntuple_test.js b/demo/node/rntuple_test.js
index 641346997..1a4d8d35b 100644
--- a/demo/node/rntuple_test.js
+++ b/demo/node/rntuple_test.js
@@ -62,7 +62,7 @@ else {
   console.log(`OK: ${rntuple.builder.columnDescriptors.length} column(s) deserialized`);
   for (let i = 0; i < rntuple.builder.columnDescriptors.length; ++i) {
     const column = rntuple.builder.columnDescriptors[i];
-    if (!column.fieldId)
+    if (column.fieldId === undefined || column.fieldId === null)
       console.error(`FAILURE: Column ${i} is missing fieldId`);
     else
       console.log(`OK: Column ${i} fieldId: ${column.fieldId} `);